Cementing tool for oil wells



2 Sheets-Sheet l INVENTOR ATTORNEY,

wd??- c. w. BREUKELMAN CEMENTING TOOL FOB. OILWELLS Filed Deo. 29, 1945Fr G. 2

WHR/5 Tm /v WBREz//fa MA /v Flai Aug- 25, 1947- c. w. BREUKELMAN2,426,164

CEMENTING' TOOL FOR OIL WELLS Filed Dec; 29, 194s 2 Sheets-Sheetl 2UHR/s ruw WERE/EL MA /V INVENTOR 4W mw ATTO R N EY Patented Aug. 26,1947 UNI-TED CEMENTING TooL Fon oIL WELLS Christian W. Brcukelman,Trinidad, British West Indies Application December 29, 194:3, Serial No.516,069

3 Claims. l.

My invention relates to cementing tools for oil wells and' hasparticular reference to tools forl sealing perforations in casing pipesin oil wells.

My invention relates to cementing tools for oilwells, and has particularreference to tools for forcing cement through perforations in casingpipes and sealing them;

Perforations are sometimes providedA in oil well casings within alimited vertical space, usually a few feet, to provide a passage throughwhich cement slurry can be forced into the annulus outside the casing toprevent the movement of fluids such as gas, oil, or water behind thecasing.

Similar perforations are sometimes provided for admitting oil or gasinto the well, and occasionally it becomes necessary to seal suchperforations as, for instance, when they lead into dry formations orformations containing salt water, etc. The usual method of sealing theperforations is by means of cement which is forced into the holes by aspecial tool.

Ordinary tools used for cementing holes in the casing pipes have adisadvantage in that they employ complicated valves requiring. rotationof the tool, special slips, etc.

My invention has for its object to providey a cementing tool in whichall the operations for opening and closing cement-admitting ports, canbe effected by the simple procedure of lowering and raising the tool,the vertical movement of the tool being used to operate slidingfrictional sleeves or valves for opening and closing" different ports oropenings.

Another object of my invention is to provide means in my tool for usingthe same for .washing out the excess cement after completion of thecementing operation.

Still another object of my invention is to provide a single tool whichcan be used for cementing' and washing out operations under alloperating conditions, and particularly those in which it is undesirableto exert additional pressure on the well below the tool during theseoperations.

My invention is more fully described in the accompanying specication anddrawings in which:

Fig. 1 is a fractional sectional view of a well casing with my tool inposition of being lowered into a casing pipe;

Fig. 2 is a similar View of mytool after it has been slightly raised tomove sliding Valves for opening ports;

Fig. 3 is a fractional sectional Viewv of a modied tool;

2 Fig. 5 is a sectional view of a modified bottom valve;

Fig. (i is a similar View oi another modification;

Figs. 6 to 11 are views of a modilied toolv in different stages ofoperation.

My cementing tool consists of a tubing I made in several sectionsconnected together by threaded couplings 22, 23, 24, 25.

The tubing is of a substantially smaller diameter than the insidediameter of a Casing pipe 3 forming walls of a well. The tubing I isprovided in the middle with an inner tube a whose upper flared-out end 2is welded to the inner walls of the tubing I, the lower end of the innertube being closed at `5. Short tubes or ducts 6 connect the lowerportion ofthe tube 4 with the annular space I between the tube 4 andcasing 3*. Sealing cups or swabs 8, 9 are placed on the tubing I ateither side of the ducts `l. The swabs are made of an elastic materialsuch as rubber. The cups are of a larger diameter than the casing pipeand are resiliently forced into the casing pipe, forming water-tightseal. They are placed opposite each other as shown so that theyeffectively resist any pressure which may be applied to the annularspace I between them. The swabs or cups are placed at a distance of fewfeet from each other or substantially farther apart than the maximumdistance between the extremeV outer perforations or shot-holes I0 in thecasing pipe.

The tubing I is also provided with vent holes II below the ilared topportion of the inner tube 4, which holes are open at all times. Thetubing I is also provided with upper vent holes or ports I2 and lowerports I3 which can be closed by slidf ing sleeves or valves I4 and I5respectively, slidably mounted on tubing I. The sleeves are of a largerdiameter than the tubing I, the annular space in the sleeves beingfilled with chevron o-r similar packing Il of self-sealing type, held atthe ends of the sleeves by threaded annular caps or flanges I8. Springclamps I9 are fastened to the sleeves and frictionally engage the innerwalls of the casing 3.

Springs I9 bear on the inner wall of the casing with suicient pressureto hold the sleeves I4, l5 to which they are attached in the stationaryposition when tubing I is moved up or down, sliding through the sleeves,until one or the other of the couplings 22, 23, 24, and 25 engage thecorresponding sleeve, whereupon the sleeve will be moved together withthe tubing in a corresponding direction. Thus, when the tubing I ismoved downward, sleeves I4 and I5, being engaged by the couplings 22 and24 respectively, will be brought to their upper operative positions asshown in Fig. 1, closing ports I2 and I3. Oil or other fluid in the wellwill be forced upward past a lower ball valve 2U into the tubing I, intoan annular space 5 within tubing I surrounding tube 4, and out throughholes II into the annular space 1, bypassing swabs 8, 9.

After the tool is placed in position, the next operation consists inforcing the uid out of the space 1' between the swabs 8, 9. This isaccomplished by pumping water into the tubing I for determining thebreak-down pressure, or pressure at which the liquid begins to ow intothe holes I3. Ports I2 are closed during this operation. The tubing, asfar down as the top of the tool, is then filled or partly filled withcement slurry. The tubing for this purpose is slightly raised, justsufficiently to open ports I2. Slurry is then pumped down the tubing,the return circulation passing through ports I2 into the annular space 1in the casing pipe. It should be noted that the port I2 must be opened,to avoid having to pump all of the iiuid in the tubing ahead of thecement through holes I3 into the formation. The position of sleeve I5during this operation is as a rule immaterial, but port I3 can be closedif desired and port I2 opened by suitable movements of the tool.

The next operation is the pressure or squeeze cementing. The tubing I islowered, closing the ports I 2. Slurry is pumped into the tubing underpressure, forcing it through the inner tube 4 and through ducts 6 intothe space 1 between the swabs 8, S. Under continuous break-downpressure, cement slurry is forced from the space 1 and through shotholes I into the space outside the casing. IThe pressure is held untilno back iiow is observed, i. e., until cement is sufficiently set. Insome instances, as in multiple-stage cementing, valved cementing portsare inserted in, and form part of the casing pipe at pre-selectedpoints. These valves prevent back-flow of cement slurry, and the toolcan be withdrawn immediately after the cement is placed behind thecasing.

It should be noted that the movement of sliding sleeve valves I4 and I5is limited by the couplings 22, 23 which limit movement of the sleeveI4, and 24, 25 which limit movement of the sleeve I5. The upper ports I2are closer to the upper coupling 22 than the lower ports I3 are to thecoupling 24 so that it is possible to raise the tubing I just enough touncover the upper ports I2 without uncovering the lower ports I3.

The ball 23 is supported in a cup-shaped expanded upper end 26 of a tube2l, sliding in a tubular casing 28 supported at the lower end of thetubing I. The upward movement of the tube 21 is limited by the coupling25 to which the casing 28 is attached, the downward movement beinglimited by a flange 29 with a central opening for the tube 21 and alsoholes 3i) therein. The depending end of the tube 21 is provided withsprings 3I frictionally engaging the inner wall of the casing pipe 3. Asealing cup-shaped member or swab 32 is tted on tube 21 below the cup26, preventing fluids in the tubing I from penetrating below the tool.

As shown in Fig. 1, the tube 21 with the ball valve 20 is brought to thetop of the casing 28 by the downward movement of the tool because of thefriction of the springs 3| against the walls of the casing pipe 3. Thetube 21 is lowered again relative to the tubing when the tool is raisedfor opening the port I 3, and that no suction or swabbing is producedbelow the too-l during this operation. The valve I uncovers the ports I3thereby equalizing pressure at both sides of the swabs 8, 9 andpreventing formation of vacuum or suction under the tool. Port I2 offersno problem when raising the tool, because port II is always open. Ifport I3 is closed, when the tool is raised, swab 9 comes into action,fiuid pressure is exerted on ball 20 through ports II, tube 21 must thenmove down in casing 23, and swabbing action is prevented while port I3is being uncovered.

A retrieving spring may be provided for the tube 21 as shown in Fig. 5so as to keep the valve 2B raised except when the tool is beingwithdrawn from the casing pipe.

Upon completion of the cementing operation, the excess cement is washedout from the inside of the tool. The tool for this purpose is raisedabove the perforations I3 (or above any, still higher, perforations, toavoid loss of washing fluid), the upward movement of the ytool willleave valves I4 and I5 resting on the couplings 23 and 25 respectively,uncovering ports I2 and I3 respectively. These ports must be closed forthe washing operation, and this can be accomplished by lowering the tooljust enough to bring the ports I2, I3 under the respective valves I4,I5. Water is then pumped down the casing pipe, past upper or invertedswab 8, through the openings 6 and up the inner tube ll into the tubingI. Since both ports I2 and I3 are closed during this operation, nopressure will be exerted on the well below the tool. It should be notedthat duct 6 is placed as far as possible from swab 8, so that themaximum washing of annulus 1 is effected.

The sliding tube 21 materially facilitates operation of the device,making it easy to pull the tool even out of deep holes.

If desired, if open formations exist below the tool, and there is noobjection to slight swabbing or suction action while opening the portsI3, the sliding valve tulbe 21 may be dispensed with and a standingvalve 34, Fig. 4, may be used.

The tool can -be also used for circulating a liquid down the tubing Iand up the casing 3, without exerting pressure on the well below thetubing. The tool for this purpose is lowered to close the ports I2 andI3 by the valves I4 and I5, then raised suiciently to close the ports I3but not I2, as shown in Fig. 2. This is possible because the port I3 islocated at a greater distance from the coupling 24 than the port I2 fromthe coupling 22 so that a small upward displacement of the tubing I issuicient for uncovering the port I2 while leaving the port I3 stillclosed. The ports I3 being closed, no liquid can penetrate into thespace under the swab 9, the return liquid iiowing up the casing 3.

If it is desired to wash out excess cement from between the swabs 8 and9, and then circulate it out up the casing 3, it is necessary rst of allto close ports I2 and I3 and pump down the casing and up the tubing pastswab 8 by a method already described. Then, when the cement has beenbrought into the lower part of the tubing I, port I2 is opened asdescribed in the previous paragraph, leaving port I3 closed, and thecement is displaced up the casing 3 by pumping down the tubing.

My tool can also replace two cement retainers, one below the shot holesas a bridge plug, and the other above for squeeze cementing.

My tool can be used for various other purposes, such as acidizing oilwells, injecting chemicals under pressure, or for perforation washing.

A modified tool is shown in Fig. 3, specially adapted for high pressurecementing. It isf provided with two swabs 36, 31- at the top, facing inthe opposite directions and of a heavy pressure type. A similar heavypressure swab 38' is placed below eementing region 'Il'. Ports 40 arealso provided with lapper valves 4I for washing out the excess cement.Water or other liquid for this purpose is pumped down the casing annulus1,

through the upper port II, into the tubing I, out the valved ports 4I,in-tothe cementing region 1', andi back through ports 6= and tubing 4and I'. The val-ve 4I may be' dispensed with for medium pressures asshown in Fig. 4, using more flexible swabs 42, 43, 44 and 45.v

The ports 4E are located between thelower swabs 44, 45 without anyvalves.

Distance between the upper and lower swabs can be adjusted. by insertingpieces 41 of varying length between the couplings in the tubing in thecementing region.

A modified tool is shown in Figs. 6 to 11. In this tool the ports I2 andI3 are at the same distance from the collars 22 and 24l but the distancebetween the upper collars 2-3 and 22 is considerably greater than thedistance between the lower collars 24 and 25:.

Position of the tool during its being lowered into the well is shown inFig. 6. The valves I4 and I5 are moved upward, resting against thecollars 22 and 24 respectively, closing both ports. When the tool islowered to a` point in which the holes Ill in the casing 3 are placedbetween the swabs 8 and 9, the breakdown pressure is determined bypumping a liquid through the inner tube IV and noting the pressure atwhich the liquid begins to flow into the formation through the holes I0.The tool is then raised as shown in Fig. 7 to uncover the port I2.Enough of the cement solution is then pumped into theinner tube fordriving the liquid ahead of the solution upward through the port I2 andthrough the annular space in the casing 3. The tool is now ready forcementing operation. I-t is lowered again as shown in Fig. 8 for closingthe ports, and more cement is pumped into the inner tube I forcing thecement at the breakdown pressure into the formation through the holes Ibetween the swabs.

Upon completion of the cementing operation the tool is raised above thecemented area as shown in Fig. 9.

During this raising operation the liquid from above the tool owsdownward through the ports I2, I I, space and port I3 so that no vacuumis formed under the tool.

For washing out the cement from the tool, the latter is lowered as shownin Fig. 10 for closing the valves. The lowering is possible withoutcreating pressure under the tool because the liquid from under` the toolflows upward through the ball valve at the bottom and through the openports II. With both ports I2 and I3 closed as shown in Fig. 11, and withthe swabs 8 and 9 above the cemented area, a liquid is pumped into theouter annular space 1, pressure of the liquid causing the upper swab 8to collapse, admitting the liquid into the space between the swabs, fromwhich it flows upward through the tubes 6, 4 and I. The upper swab actsas a valve in this case, being of a convex shape.

It should be noted that the packing in the valve I4 must resist pressurefrom within and from without the valve, while the packing in the valveI5 must resist onlypressure from within the tool.

It is understood that my cementing tools for Cil `oil Wells may befurther modified without` de,-

parting from the spirit of the invention, as set forth in the appendedclaims.

I claim as my invention:

1. A cementing tool for oil wells` comprising a tubing constructed to beplaced in a casing of a well, the tubing being of a substantiallysmaller diameter than the casing; a tubular member of a still smallerdiameter within the tubing, the upper end of the tubular membercommunicating with the tubing and being narod-out and attached to theinner wall of the tubing, forming a seal between the tubular member andthe tubing; a checkY Valve closing the lower end of the tubing againstdownward ow of huid; the lower end of the tubular member being closed tocommunication with the tubing; tubular ducts connecting the tubularmember with the outside of the-tuk ing; sealing swabs on the tubingabove and below the outer openings of the tubular ducts, said swabsbeing spaced apart a distance greaterthan the length of that portion ofthe .casing occupied by holes to be cemented; the tubing havingpermanently open ports abovethe sealing swabs and below the flared-outlend of the tubular member, and having additional ports above and belowthe sealing swabs; sleeves slidably supported on the tubing for closingsaid additional ports; frictional members extending from the sleeves andengaging the inner wall of the casing forretaining the sleevesstationary when the tubing is moved; the said additional ports above thswabs being also above the flared-out end of the tubular member, thesleeves being adapted to close said additional ports when the tubing ismoved downwardly, and to open said additional ports when the tubing ismoved upwardly; an enlarged tube depending from thelowerend of thetubing; a sliding tube in the enlarged tube and extending through thelower end of the enlarged tube; a sealing swab at the upper end of thesliding tube engaging the inside walls of the enlarged tube; means onthe outwardly extending portion of the sliding tube for frictionallyengaging the inner surface of the casing; and means to limit themovements of the sliding tube in the enlarged tube, the distance ofmovement of the sliding tube being comparable to the distance ofmovement of the tubing for opening the ports, the check valve beingarranged to be opened by inwardly flowing well huid when lowering thetool for admitting the fluid from the well into the tubing, the well uidflowing outwardly through said permanently open ports into the casing.

2. A `cementing tool for oil wells comprising a tubing constructed to beplaced in a casing of a well, the tubing being of a substantiallysmaller diameter than the casing; a tubular member of a still smallerdiameter within the tubing, the upper end of the tubular membercommunicating with the tubing and being flared-out and attached to theinner wall of the tubing, forming a seal between the tubular member andthe tubing; tubular ducts connecting the tubular member with the outsideof the tubing, sealing swabs on the tubing above and below the outeropenings of the tubular ducts; said sealing swabs being spaced apart adistance .corresponding to the length of that portion of the casingoccupied by holes to be cemented; the tubing having permanently openports above the sealing swabs and below the flared-out end of thetubular member, and having additional ports .above and below the sealingswabs, the additional port above the swabs being also above theflared-out end of the tubular member; sleeves slidably supported on thetubing for closing said additional ports; frictional members extendingfrom the sleeves to the inner wall of the casing for retaining thesleeves stationary when the tubing is moved; an enlarged tube dependingfrom the lower end of the tubing; a sliding tube in the enlarged tubeand' extending through the lower end of the enlarged tube; a sealingswab at the upper end of the sliding tube engaging the sides of theenlarged tube; an upwardly and downwardly closing check valve at ltheupper` end of the sliding tube for preventing downward flow of theiluids through the tubing; frictional means on the outward extension ofthe sliding tube for engaging the inner surface of the casing; and meansto limit the movements of the sliding tube in the enlarged tube.

. 3. A cementing tool for oil Wells comprising a tubing constructed tobe placed in a casing of a wall, the tubing being of a substantiallysmaller diameter than the casing; a tubular member of a still smallerdiameter within the tubing, the upper end of the tubular membercommunicating with the tubing and being flared out and attached to ftheinner wall of the tubing, forming a seal between .the tubular member andthe tubing, tubular ducts connecting the closed end of the tubularmember with the space outside of the tubing; sealing swabs on the tubingabove and below the outer openings of the tubular ducts for sealing offan annular space in the casing between the ca-sing and tubing above andbelow the lower end of the tubular member, said swabs being spaced aparta distance greater than the length `of the portion of the veasingoccupied by holes to be cemented; the tubing having permanently openports above and sealing swabs under the enlarged end of the tubularmember and additional ports above the open ports and below the 8 lowerswabs respectively, the additional upper port being above the flared outend of the tubular member; sleeves slidably supported on the tubing forclosing the upper and lower additional ports respectively; frictionalmembers extending from the sleeves to the inner Walls of the casing forretaining the sleeves stationary when the tubing is moved; upper collarson the tubing above the additional ports for engaging the sleeves whenfthe tubing is moved downwardly in which position of the sleeves theadditional ports are closed by the sleeves; lower collars on the tubingbelow the additional ports and spaced therefrom'for engaging the sleeveswhen the tubing is moved upwardly in which position of the sleeves theadditional ports are opened, the distance between the upper and lowercollars on that portion of the tubing above the swabs being greater thanthe distance between the collars below the swabs for enabling the loweradditional ports to be closed ahead of the upper additional ports whenthe tubing is moved upwardly; and means including a downwardly closingcheck valve at the bottom of the tubing, for admitting a fluid from thewell into the casing through permanently open ports when the tool isbeing lowered.

CHRISTIAN W. BREUKELMAN.

REFERENCES CITED The following references are of record. in the ille ofthis patent:

UNITED STATES PATENTS Number Name Date 2,341,832 Verheul et al Feb. 15,1944 2,235,318 Halliburton Mar. 18, 1941 2,308,072 Granger Jan. 12, 19432,214,121 Coste1lo Sept. 10, 1940 2,360,311 Ausburn et al Oct. 1'7, 1944

